Mobile broadband usage continues to grow rapidly throughout the world. This dramatic growth has placed pressure on Mobile Network Operators (MNOs) to ensure adequate capacity and performance, and on regulators to provide access to the additional spectrum critical to capacity expansion.
Spectrum, a highly essential resource for wireless communications, is a finite resource that is in high demand due to the dramatic growth in wireless mobile data traffic. From license perspective, spectrum utilized in the wireless communication field may be divided into: licensed spectrum for commercial services which is exclusive, high quality yet costly; and unlicensed spectrum which is not exclusive and low cost. Under the definition, spectrum sharing is the collective use of a given portion, i.e., frequency band, of the licensed spectrum or the unlicensed spectrum by two or more parties.
As considering spectrum sharing, there must be interference among the parties due to the collective use of spectrum, whether the spectrum sharing is applied to the licensed spectrum or the unlicensed spectrum. It is undesired that the interference among the parties is serious enough for destroying the spectrum sharing. Therefore, it is important in the art to avoid such interference as destroying the spectrum sharing among the parties in a spectrum sharing system.